Development of a reader for the routine analysis of CR-39 fast neutron dosemeters: improvement of the dosimetric performance using automatic vision and motion tools

At the personal dosimetry service of the ENEA Radiation Protection Institute, a fast neutron dosemeter based on chemically etched CR-39 (Poly Allyl Diglycol Carbonate) is operating since more than 20 years. Since then the track counting has been performed with a system consisting of a microscope, a video camera and an image analyser. A new automatic analysis system has been developed, based on automatic motion and vision tools and the programming language Labview 6, from National Instruments. The system selects the correct number of reading fields on the basis of a preliminary scan of the dosemeter, therefore operating motion and vision procedures in order to perform the analysis. For each reading field the system collects the track area distribution to which a previously optimised algorithm is applied, in order to correct the energy dependence of the response. For each dosemeter, a record containing the barcode and all data necessary for assessing the personal dose equivalent is stored in a routine file. Taking advantage of automatic vision and motion, a CR-39 reader with innovative features in terms of reproducibility, velocity and accuracy is now available even for the routine purposes of dosimetric services.     

Multimodal Interfaces for Cell Phones and Mobile Technology

By modeling users' natural spoken and multimodal communication patterns, more powerful and highly reliable interfaces can be designed that support emerging mobile technology. In this paper, we highlight three different examples of research that is advancing state-of-the-art mobile technology. The first is the development of fusion-based multimodal systems, such as ones that combine speech and pen or touch input, which are substantially improving the robustness and stability of system recognition. The second is modeling of multimodal communication patterns to establish open-microphone engagement techniques that work in challenging multi-person mobile settings. The third is new approaches to adaptive processing, which are able to transparently guide user input to match system processing capabilities. All three research directions are contributing to the design of more reliable, usable, and commercially promising mobile systems of the future.     

Vision system for three-dimensional position measurement based on stereo disparity

A stereo disparity-based range finding technique was developed for measuring three-dimensional coordinates of object points. It used an image-matching algorithm which functionally consisted of scene reduction, epipolar line selection, and features matching. Experiments implementing this technique were performed on an industrial vision system. An error analysis indicated that image resolution was the major source of measurement inaccuracy.     

一种图象方向检测方法

在图象处理、模式识别中,经常要提取轮廓的走向、灰度电平变化方向的参数。在以往的方法中,常常采用不同方向的模板,对图象进行卷积运算,然后据所得的结果判别其方向。然而随着分辨率的提高,模板的数量也增加,卷积运算也增加,因此一般只能选取8个模板.本文提出一种比较法,它根据图象邻近象素点比较的结果,以权函数表示,其最终结果可获得16个方向的分辨率,由于没有乘法运算,因而运算速度高,易于硬件实现。     

Non-linear response of liquid crystal spatial light modulators

This technical note outlines the results of a series of experiments performed on two spatial light modulators. The two modulators were a Hughes Corporation LCLV and an optically-addressed ferroelectric liquid crystal SLM fabricated by the University of Colorado at Boulder and Displaytech. These experiments were performed to determine the modulated response of the read beam as a function of the write light intensity.     

Measurement of Principal-Stress Directions from Photoelastic Experiment Using Generalized Phase-Shift Method

A generalized phase-shift method is developed for automatic measurement of principal-stress directions in the whole field of a model from photoelastic experiments. This method uses a set of light intensities obtained from the rotation of polaroids in dark-field plane polariscopes at each point. To investigate the accuracy of the measurement, time-series light intensity curves with different noise and different numbers of data which constitute the curves are used in computer simulation. The error of the measurement of the principal-stress directions obtained by the method is not greatly affected by noise when the number of data exceeds 50. This method is applied to a circular disk subjected to a concentrated load. The principal-stress directions obtained by the method are found to be in good agreement with the theory.Presented at 1996 International Workshop on Interferometry (IWI ‘96), August 27–29, Saitama, Japan.     

线性图像处理的2D离散状态空间切换模型的能控性

研究了线性图像处理的Roesser模型的能控性,并讨论了相应的切换模型的能控性.给出一个最小不变子空间,得到了2D离散状态空间切换模型的一个能控性判据.     

空间信息融合处理技术在现代战争中的作用

信息技术与航空航天技术的发展,使利用卫星从空间进行侦察与监视成为现代战争收集敌方情报的主要手段之一。充分运用信息融合与处理技术对空间卫星多源信息进行综合分析与处理,在现代战争中发挥着越来越大的作用。     

Ultimate quantum limits for resolution of beam displacements

We compare two high sensitivity techniques which are used to measure very small displacements of physical objects by optical techniques: the interferometric devices, measuring longitudinal phase shifts, and the devices used to monitor transverse displacement of light beams. We detail the differences and the similarities for the quantum limits on the resolution of both systems. In both cases squeezed light can be used to resolve beyond the standard quantum limit and number correlated states allow us to reach the “Heisenberg” limit. Received 12 September 2002 Published online 21 January 2003     

光学零件超声波清洗的应用现状及其发展

本文在概述超声波清洗机理之后，着重介绍了光学零件超声波清洗的应用现状及光学零件超声波清洗用的清洗剂、脱水剂、干化剂等清洗辅料的几个进展阶段，以及当前清洗辅料的研究动态及面临课题。